The present invention relates to a novel bag within which to reconstitute powdered milk, and more particularly relates to such a bag and its method of construction for use in dispensing powdered milk commercially, for example in institutions and the like, through conventional commercial milk dispensing cabinets.
In my earlier U.S. Pat. No. 4,651,898, I have described an apparatus for controlling the flow of two streams of whole milk and reconstituted powdered milk simultaneously, from commercial milk dispensing cabinets found in cafeterias, institutions and the like, to provide a palatable milk product. The whole milk and reconstituted powdered milk are held in standard (for example, five gallon) dairy bags having a flexible spigot or snip tube extending from an opening by which the bag had been previously filled. To obtain a five gallon bag of reconstituted powdered milk, conventionally a bag with the appropriate amount of dry powdered milk held within may be provided and about five gallons of tap water added through the opening where the snip tube is attached. The snip tube would then be snapped into a permanent position sealing the water inside the bag.
The problem with such a method is that health regulations may require the water to be pre-chilled for example to 40.degree. F. or below to minimize bacterial growth and the like, before reconstituting the milk. The water being added to the bag of dry powdered milk may well be much warmer than that, creating a potential health hazard until the milk becomes chilled down sufficiently.
A considerable effort has been made in recent years by milk producers, and particularly by those marketing powdered milk, to find technology which will permit powdered milk to be reconstituted commercially under hygienic conditions with water which has been properly pre-chilled.
In order to achieve this end, in accordance with the present invention, a compartmented package, appropriate to mix within skim milk and water, has been developed.
Compartmented packages are, generally speaking, well-known in the prior art. Examples of compartmented packages for various applications have been described and illustrated for example in the following references: U.S. Pat. No. 2,157,169 of Foster issued May 9, 1939; U.S. Pat. No. 3,596,801 of Barnack issued Aug. 3, 1971; U.S. Pat. No. 3,429,429 of Poitras issued Feb. 25, 1969; U.S. Pat. No. 1,332,985 of Jarrett issued Mar. 9, 1920; U.S. Pat. No. 2,727,987 of Kabnick issued Sept. 10, 1929; U.S. Pat. No. 2,647,681 of Paoli issued Aug. 4, 1953; U.S. Pat. No. 2,824,010 of Pedersen issued Feb. 18, 1958; U.S. Pat. No. 2,885,104 of Greenspan issued May 5, 1959; U.S. Pat. No. 3,156,369 of Bowes, et al issued Nov. 10, 1964; U.S. Pat. No. 3,779,372 of Gil de Lloret issued Dec. 18, 1973; U.S. Pat. No. 3,813,54 of Gilliam issued May 28, 1974; U.S. Pat. No. 4,519,499 of Stone et al. issued May 28, 1985 and U.S. Pat. No. 4,548,606 of Larkin issued Oct. 22, 1985.
Of particular interest in these references is U.S. Pat. No. 2,157,169 of Foster which describes and illustrates a flexible bag of canvas or similar material containing one of the constituents for a heat producing chemical reaction, and, within that bag, a second compartment of readily frangible material such as glacine paper for separate storage of the other of the components. The mouth of the inner bag is stitched along one edge of the outer bag. By destroying the partition between the two compartments, the constituents are permitted to be mixed.
One of the difficulties experienced with mixing of instant powdered milk is to ensure that there is a quick release of the powder into the water, with a maximum dispersal of the instant powder. The dual compartment arrangement proposed by Foster would be unsuitable for such application, if powder were held in the inner bag, since powder would not readily come out of that bag without kneading and the like. As well, once that inner bag is opened, much of the integrity of the inner bag remains, so that there would be a tendency for water to seep into the inner bag and only partially dissolve the milk powder, creating a paste.
Barnack U.S. Pat. No. 3,596,801 and Poitras U.S. Pat. No. 3,429,429 describe and illustrate alternative forms of flexible walled containers with separate interior compartments.
None of these prior art references however, provides or suggests a solution to the problem of providing a structure for mixing in large volumes at the appropriate time water and powdered milk for commercial purposes. It is thus an object of the present invention to provide such a structure and method of doing same. It is a further object of the present invention to provide a structure within which powdered milk may be reconstituted which is easy to use by relatively untrained staff, and which consistently will provide a quality product of well-mixed reconstituted milk. It is a further object of the present invention to provide such a structure which is both hygienic to use and will make it possible to readily reconstitute the dry powdered milk and water only after the water has been sufficiently chilled to satisfy health regulations.